Compatible with/replacement for Hustler Z4 XR7 Z PTO Blade Clutch 787366K -NEW Heavy Duty FatBoy Series This is an upgraded version of the OEM Clutch. Xtreme Mower Clutches, uses machined billet pulleys, upgraded bearings with high temperature grease, and a triple protected wire harnesses. The proprietary Xtreme Cool Coil technology reduces temperature to extend clutch life, and has a replaceable pulley bearing. Every Xtreme Clutch comes with a watertight integrated wire harness - PLUG and PLAY ! Xtreme Mower Clutches is a registered trademark of Extreme Mower Clutches Inc. (XMCI) of Boca Raton Florida. XMCI does not imply any association or affiliation with any OEM Manufacture including Warner Electric, Ogura Industrial Corp., John Deere, Exmark/Toro, Hustler, Husqvarna, Cub Cadet, or any of its associates or affiliates, trademarks or copyrights. XMCI also states “OEM Upgrade” or “Warner Upgrade” only refers to the billet pulley, the use of stainless steel braking rivets, replaceable pulley bearing, Xtreme wire protection system, and Cool coil technology, most of which are unique to the Xtreme Mower Clutch product line.